[. . . ] Safety notes Installation and connection guide Disconnect the negative terminal of the car battery during installation and connection. [. . . ] installation: Hold the control unit to the steering wheel and find the most suitable mounting position. Attach the fixing plate to the steering wheel using the flexible holding strap. (Move the strap through the slot in the fixing plate, pull tishtly and press into the detent noses. ) If necessary, attach the compensation rubber elements to the inner side of the control unit, depending on the steering wheel diameter. 2 (see arrow 1), engage it, and turn it to the left (push back, see arrow 2). Finally press down firmly and lock using the attached tool or a small screwdriver or pen, see fig. [. . . ] connect the IR remote control cable across the car radio and the existing wire harness. [. . . ]